Method for internet protocol based multimedia subsystem registration and device, communication device, and storage medium

ABSTRACT

The disclosure relates to a method for Internet Protocol based Multimedia Subsystem (IMS) registration and device, a communication device, and a storage medium. The method for IMS registration includes determining whether a network side supports an IMS service; acquiring, based on an IMS Access Point Name (APN), an address for the IMS registration when the network side supports the IMS service; performing the IMS registration based on the acquired address for the IMS registration; and initiating an IMS re-registration when the IMS registration fails.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is filed based upon and claims priority to ChinesePatent Application No. 201910907670.4, filed on Sep. 24, 2019, theentire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to the technical field of communications,and more particularly, to a method for Internet Protocol MultimediaSubsystem (IMS) registration and device, a communication device, and astorage medium.

BACKGROUND

An IMS service includes a voice call service. However, before the voicecall service is used, an IMS registration needs to be performed. Afterthe IMS registration is successful, a voice call in the IMS service canbe obtained through an IMS technology. However, in the related art, theIMS registration of a terminal sometimes fails. If the IMS registrationfails, a voice call function in the IMS service cannot be used, whichmay cause the voice call quality of the terminal to be impaired.

For example, the voice service in the IMS service includes: Voice overLong Term Evolution (VoLTE), which is a voice call service that canprovide high call quality. With the gradual use of 4^(th) Generation(4G) network or 5^(th) Generation (5G) network, 2^(nd) Generation (2G)network and 3^(rd) Generation (3G) network will be retired. At thistime, the voice call function of VoLTE becomes more and more important.After the IMS registration is successful, the high call quality of VoLTEcan be enjoyed. If the IMS registration fails or is not performed, theterminal cannot use the voice call function of VoLTE.

SUMMARY

This Summary is provided to introduce a selection of aspects of thepresent disclosure in a simplified form that are further described belowin the Detailed Description. This Summary is not intended to identifykey features or essential features of the claimed subject matter, nor isit intended to be used to limit the scope of the claimed subject matter.

Aspects of the disclosure provide a method for Internet ProtocolMultimedia Subsystem (IMS) registration, the method being applied to aterminal. The method includes determining whether a network sidesupports an IMS service; acquiring, based on an IMS Access Point Name(APN), an address for the IMS registration when the network sidesupports the IMS service; performing the IMS registration based on theacquired address for the IMS registration; and initiating an IMSre-registration when the IMS registration fails.

In an example, when initiating the IMS re-registration, the methodfurther includes initiating the IMS re-registration when a number oftimes that the IMS registration is performed does not reach a firstpreset threshold.

According to an aspect, the method further includes re-acquiring anaddress for an IMS registration when the number of times that the IMSregistration is performed reaches the first preset threshold; andinitiating the IMS registration based on the re-acquired address for theIMS registration.

In an example, when re-acquiring the address for the IMS registration,the method further includes determining whether a number of times thatacquisition for the address the IMS registration is performed reaches asecond preset threshold; and re-acquiring the address for the IMSregistration when the number of times that the acquisition is performeddoes not reach the second preset threshold.

According to an aspect, the method further includes controlling theterminal to enter a flight mode when the number of times that theacquisition is performed reaches the second preset threshold;controlling the terminal to exit the flight mode after the terminalenters the flight mode for a predetermined duration; and performingnetwork attach after the terminal exits the flight mode, whereindetermining whether the network side supports the IMS service comprisesdetermining whether the network side supports the IMS service after theterminal is attached to a network.

According to another aspect, the method further includes receiving areason for a failure of the IMS registration; and determining the firstpreset threshold based on the reason.

In an example, when The determining the first preset threshold, themethod further includes determining that the first preset threshold hasa first value when the reason for the failure of the IMS registration isthat a registration request of the IMS registration is lost; anddetermining that the first preset threshold has a second value when thereason for the failure of the IMS registration is that an IMS serverrefuses to register, wherein the second value is less than the firstvalue.

According to an aspect, the method further includes sending an attachrequest to the network side; receiving an attach acceptance from thenetwork side based on the attach request; and determining whether thenetwork side supports the IMS service based on an IMS service supportindication field carried in the attach request.

In an example, when acquiring the address for the IMS registration whenthe network side supports the IMS service, the method further includessending a Public Data Network (PDN) connection request to the networkside when the network side supports the IMS service; and receiving aconnection response from the network side based on the PDN connectionrequest, wherein the connection response carries an address for the IMSregistration.

Aspects of the disclosure also provide a device for Internet ProtocolMultimedia Subsystem (IMS) registration, the device being applied to aterminal. The device includes a processor and a memory configured tostore instructions executable for the processor. The processor isconfigured to determine whether a network side supports an IMS service;acquire, based on an IMS Access Point Name (APN), an address for the IMSregistration when the network side supports the IMS service; perform theIMS registration based on the acquired address for the IMS registration;and initiate an IMS re-registration when the IMS registration fails.

Aspects of the disclosure also provide a non-transitorycomputer-readable storage medium storing instructions that, whenexecuted by a processor of a terminal, cause the terminal to determinewhether a network side supports an IMS service; acquire, based on an IMSAccess Point Name (APN), an address for the IMS registration when thenetwork side supports the IMS service; perform the IMS registrationbased on the acquired address for the IMS registration; and initiate anIMS re-registration when the IMS registration fails.

It is to be understood that both the foregoing general description andthe following detailed description are illustrative and explanatory onlyand are not restrictive of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate aspects consistent with thedisclosure and, together with the specification, serve to explain theprinciples of the disclosure.

FIG. 1A is a flow diagram illustrating a method for IMS registration,according to an exemplary aspect of the present disclosure.

FIG. 1B is a flow diagram illustrating a method for IMS registration,according to an exemplary aspect of the present disclosure.

FIG. 2 is a flow diagram illustrating a method for IMS registration,according to an exemplary aspect of the present disclosure.

FIG. 3 is a flow diagram illustrating a method for IMS registration,according to an exemplary aspect of the present disclosure.

FIG. 4 is a structural diagram illustrating a device for IMSregistration, according to an exemplary aspect of the presentdisclosure.

FIG. 5 is a structural diagram illustrating a terminal, according to anexemplary aspect of the present disclosure.

The specific aspects of the present disclosure, which have beenillustrated by the accompanying drawings described above, will bedescribed in detail below. These accompanying drawings and descriptionare not intended to limit the scope of the present disclosure in anymanner, but to explain the concept of the present disclosure to thoseskilled in the art via referencing specific aspects.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary aspects, examples ofwhich are illustrated in the accompanying drawings. The followingdescription refers to the accompanying drawings in which the samenumbers in different drawings represent the same or similar elementsunless otherwise represented. The implementations set forth in thefollowing description of exemplary aspects do not represent allimplementations consistent with the disclosure. Instead, they are merelyexamples of devices and methods consistent with aspects related to thedisclosure as recited in the appended claims.

As illustrated in FIG. 1A, the present aspect provides a method for IMSregistration, applied to a terminal. The method includes the followingoperations.

In S11, it is determined whether a network side supports an IMS service.

In S12, when the network side supports the IMS service, an address forthe IMS registration is acquired according to an IMS APN.

In S13, the IMS registration is performed according to the acquiredaddress for the IMS registration.

In S14, when the IMS registration fails, an IMS re-registration isinitiated.

The method for IMS registration provided in the present aspect isapplied to a terminal in an IMS service. For example, the terminal is aterminal which supports VoLTE. Specifically, the terminal may include: amobile phone, a tablet, a wearable device, a smart home or smart officeterminal, and the like.

The IMS service provides high-quality voice services, which includeVoLTE and Voice over WiFi (VoWiFi).

The network side is relative to the terminal. The terminal is a wirelesscommunication terminal, and performs information interaction with thenetwork side through a wireless link. The network side may generallyrefer to a network connection, other than any terminal, that supports acommunication between the terminal and other devices. For example, thenetwork side includes: a wireless network and/or a core network. Thewireless network includes access network elements, and typical accessnetwork elements include various types of base stations and/or WiFihotspots.

In the aspect of the present disclosure, in S11, it is mainly determinedwhether the core network supports the IMS service. Network elements ofthe core network may include, but is not limited to, a Call SessionControl Function (CSCF), an application server, a Home Subscriber Server(HSS), and the like. The terminal may be connected to the core networkthrough an access network.

When it is determined that the network side supports the IMS service andthe terminal is a terminal that supports the IMS service, in order toensure the voice call quality of the terminal, the terminal triggers theacquisition for the address for the IMS registration by itself. Theprocess of acquiring the address for the IMS registration may also bereferred to as the process of establishing the IMS APN.

The address for the IMS registration may include: an IP address of anIMS server and an IP address of the terminal. When performing an IMSregistration, an IMS registration request is sent with the address ofthe IMS server as a destination address and the IP address of theterminal as a source address, and a registration response to the IMSregistration returned by the IMS server according to the IMSregistration request is received.

The IMS APN for acquiring the address for the IMS registration may berecorded in the terminal in advance, so the terminal may acquire the IMSAPN in advance before acquiring the address. The operation of acquiringthe IMS APN may include:

configuration parameters of a mobile network data service are acquired.Here, the configuration parameters may include various types of APNswhich are pre-configured, and different types of mobile network dataservices may have different APNs. The APN for mobile network data of theIMS service in the aspect of the present disclosure is referred to as anIMS APN.

Specifically, the configuration parameters are pre-configured in theterminal or received from a mobile network, and the APN corresponding tothe IMS service in the configuration parameters is queried based on aservice label of the IMS service, the IMS APN thereby is obtained.

For example, a communication operator may set one or more Public LandMobile Networks (PLMNs), and different PLMNs may correspond to differentAPNs. Thus, the configuration parameters may be preset in a mobileterminal or a Mobile Subscriber Identification (SIM). Therefore, in S12,the IMS APN may be obtained by reading a configuration file, whichcontains the configuration parameters, in the SIM.

The IMS registration may include that:

the terminal sends an IMS registration request to the network sideaccording to the acquired address for the IMS registration; and

a registration response returned by the network side according to theIMS registration request is received.

A result of the IMS registration may be carried in the registrationresponse.

When performing the IMS registration, the interaction of a registrationrequest and a registration response may be performed based on a SessionInitiation Protocol (SIP).

Through the IMS registration, the terminal may obtain an authorizationto use VoLTE. Thus, the network side may verify subscription informationof the IMS service for the IMS service of the terminal, and then theterminal obtains an ability to acquire the IMS service through thenetwork side. For example, the terminal obtains the function of usingVoLTE through the network side. At the same time, the terminal may alsoobtain usage parameters of the IMS service through the IMS registration.The usage parameters include, but are not limited to, one of:

identification information, such as a call identity which is used in theIMS service; and

routing information, such as a routing node(s) that is(are) to be passedthrough when sending and receiving service data of the IMS service ofthe terminal. The routing node may be a charging node for IMS servicecharging, a flow control node for flow control, or a policy node for IMSservice control.

In summary, the terminal obtains various usage parameters and theauthorization to use the IMS registration through the IMS registration.

The result of the IMS registration may include: registration success andregistration failure.

When the IMS registration is successful, the terminal may use the IMSservice subsequently, and the process of the IMS registration ends.

When an IMS registration fails, an IMS re-registration is initiated,thereby avoiding a phenomenon that the CMS registration is no longerperformed after a single IMS registration fails such that the IMSregistration of the terminal will maintain a failure result, which willcause the terminal unable to use a voice call function of VoLTE based onthe IMS registration. Therefore, according to the technical solutionprovided in the aspects of the present disclosure, the time periodduring which the terminal is in a failure state of IMS registration isreduced, the available time period for the voice call function of VoLTEis prolonged, and the voice call quality of the terminal is ensured.

In some aspects, S14 may include that: when the number of times that theIMS registration is performed does not reach a first preset threshold,an IMS re-registration is initiated.

In some other aspects, as illustrated in FIG. 1B, the method may furtherinclude the following operations.

In S15, when the number of times that the IMS registration is performedreaches the first preset threshold, an address for the IMS registrationis re-acquired, and an IMS registration is initiated according to there-acquired address for the IMS registration.

In the aspect of the present disclosure, the first preset threshold maybe any positive integer. Specifically, the first preset threshold may beequal to 1 or may be a positive integer not less than 2. When the firstpreset threshold is a positive integer greater than or equal to 2, theterminal records the number of times that the IMS registration isperformed. When the number of times that the IMS registration isperformed does not reach the first preset threshold, it is consideredthat the condition for re-acquiring the address for the IMS registrationis not met, but an IMS re-registration is performed preferentially.Thus, through the IMS re-registration, the failure of the IMSregistration during the IMS registration process is preferentiallyeliminated, thereby reducing the number of times that unnecessaryacquisition for an address is performed.

If the IMS registration fails, in the aspect of the present disclosure,it is further determined whether a condition for re-acquiring theaddress is met. If the condition for re-acquiring the address is met, anIMS APN may be automatically re-acquired and an IMS registrationaccording to the re-acquired address is triggered. Thus, if the IMSregistration fails due to an error of address acquisition, the terminalautomatically triggers the re-execution of the IMS registrationaccording to the re-acquired address, such that the terminal completesthe IMS registration. Of course, in some aspects, the addressacquisition itself has no error, but the IMS registration still fails.At this time, the IMS re-registration may also be triggered by theaddress re-acquisition, so that the failure of the IMS registrationwhich is caused by other reasons in the IMS registration may also beeliminated, thereby reducing the duration in which the terminalmaintains the failure of the IMS registration, and ensuring the normaluse of the IMS service of the terminal.

For example, when the first preset threshold is N, after an acquisitionfor the address for the IMS registration is completed, when N IMSregistrations fail, it is determined that the condition for re-acquiringaddress is met, and the terminal automatically re-acquires the addressfor the IMS registration. Thus, one acquisition for the address by theterminal can trigger the terminal to perform N IMS registrations. Whenthe nth IMS registration is successful, the current address acquisitiontriggers the execution of N IMS registrations. n is a positive integerless than N. It is to be noted that when the IMS service is implementedafter the terminal completes one IMS registration, it is found that theIMS service fails to be provided, then the remaining number of IMSre-registrations triggered by the current address acquisition may beresumed, thereby reducing the duration in which the terminal is in anfailure state of the IMS registration as much as possible.

In some aspects, as illustrated in FIG. 2, S15 may include the followingoperations.

In S151, it is determined whether the number of times that acquisitionfor the address for the IMS registration is performed reaches a secondpreset threshold.

In S152, when the number of times that the acquisition is performed doesnot reach the second preset threshold, an address for the IMSregistration is re-acquired.

In some aspects, a second preset threshold is set for the acquisition ofthe IMS APN. After the terminal is powered on currently or attached tothe network currently, if the number of times that acquisitions for theaddress is performed has reached the second preset threshold, it may beimpossible to eliminate fault by the acquisition for the address for theIMS registration. Therefore, on the one hand, in order to eliminate thefault of the IMS registration success as much as possible, and on theother hand, in order to reduce the number of times that unnecessaryacquisition for address for the IMS registration is performed as much aspossible, it is determined whether the number of times that acquisitionfor the address is performed has reached the second preset thresholdafter the terminal is powered on currently or attached to the networkcurrently. The re-acquisition for the address for the IMS registrationis performed only when the number of times that the acquisition isperformed does not reach the second preset threshold.

The second preset threshold may be any positive integer. For example,the second preset threshold may be a positive integer of 1, 2 or more.

The second preset threshold may be an empirical value obtained accordingto a troubleshooting experience, or may be an experimental valueobtained based on an experimental test. The second preset threshold maybe obtained in various manners, which will not be further limited in theaspect of the present disclosure. The second preset threshold may bewritten to the terminal in advance, or may be delivered to the terminalin advance through an access network element such as a base station. Forexample, the second preset threshold is written into a SIM card. In someother aspects, the terminal may dynamically configure the second presetthreshold according to its own state. For example, the terminalconfigures the second preset threshold according to its remaining power.The remaining power is positively related to the second presetthreshold, that is, the higher the remaining power is, the larger thesecond preset threshold is.

In some aspects, as illustrated in FIG. 3, the method further includesthe following operations.

In S01, when the number of times that the acquisition is performedreaches the second preset threshold, the terminal is controlled to entera flight mode.

In S02, after the terminal enters the flight mode for a predeterminedduration, the terminal is controlled to exit the flight mode.

In S03, after the terminal exits the flight mode, network attach isperformed.

S11 may include that: after the terminal is attached to a network, it isdetermined whether the network side supports the IMS service.

The flight mode is a mode in which the terminal cannot communicate. Inthe flight mode, the terminal leaves the network. When it is found thatthe number of times that the acquisition is performed during the currentround of IMS registration process reaches the second preset threshold,the terminal will be controlled to enter the flight mode to furtherachieve the success of the IMS registration. After the terminal entersthe flight mode, the terminal will leave the network. After the terminalenters the flight mode, it will switch out of the flight mode. Thepredetermined duration may be an arbitrary duration set in advance. Forexample, the predetermined duration may be a duration of 0.5 s, 1 s, 2s, or the like.

In some aspects, in order to reduce the duration in which the flightmode makes the terminal unable to communicate as much as possible, thepredetermined duration may be less than or equal to 3 s or 5 s.

After the terminal exits the flight mode, it will automatically searchfor the network again and be attached to the network. After the terminalis attached to the network, a new IMS registration process will bere-triggered. Firstly, after the terminal is attached to the network,S11 is automatically performed, so as to re-determine whether thenetwork side supports the IMS service.

In some aspects, after the network attach, the execution starts withS12. However, the terminal may be mobile. After moving during thereattach process, the terminal may move into a network coverage rangethat does not support the IMS service. In order to eliminate that therepeated IMS registration is caused by a confirmation error of a resultof whether the network side supports the IMS service, after the terminalis attached to the network, it may be re-determined whether the networkside supports the IMS service to trigger the current round of IMSregistration. A round of IMS registration may include up to Macquisitions for the address for the IMS registration, and up to N*M IMSregistrations. M may be the second preset threshold, and N may be thefirst preset threshold.

In some aspects, the first preset thresholds corresponding to any reasonfor a failure of the IMS registration may be the same. For example, thefirst preset thresholds corresponding to the IMS registration failurescaused by the server rejection and by the transmission failure of theIMS registration request may be the same or different.

However, in order to reduce unnecessary repeated IMS registrations, thepresent disclosure dynamically sets the first preset threshold accordingto the reason for registration failure.

For example, the method may further include that: a reason for a failureof the IMS registration is received; and the first preset threshold isdetermined according to the reason.

Further, the operation that the first preset threshold is determinedaccording to the reason may include that:

when the reason for the failure of the IMS registration is that aregistration request of the IMS registration is lost, it is determinedthat the first preset threshold has a first value; and

when the reason for the failure of the IMS registration is that an IMSserver refuses to register, it is determined that the first presetthreshold has a second value, the second value is less than the firstvalue.

In some aspects, the loss of a registration request may be due to thefact that the current network connection is unstable, and theregistration request drops packets during the transmission process,resulting in that the registration request is not successfullytransmitted to the IMS server.

In some other aspects, the loss of a registration request may be due tothe fact that a destination address carried in the registration requestis wrong or tampered with.

Possible reasons for the IMS server to refuse the IMS registration ofthe terminal may be as follows:

the IMS server is overloaded;

software and/or hardware abnormalities occur on the IMS server;

the verification of the IMS registration of the terminal is different.For example, the server determines that the current terminal requestingregistration may be an illegal terminal. For example, when it isdetermined that the terminal is a terminal in a blacklist, the terminalis determined as an illegal terminal.

The first value is set to be greater than the second value according tothe probability that the faults corresponding to two reasons areeliminated, so that on the one hand, unnecessary IMS registrations arereduced, and on the other hand, the IMS registration of the terminal canbe made as successful as possible.

For example, a plurality of IMS APNs may be configured in the terminal.When the IMS registration triggered by an address for the IMSregistration for which an IMS APN is acquired fails, the terminal pollsthe next IMS APN according to the address for the IMS registration whichis used in the failed IMS registration. Different IMS APNs correspond todifferent IMS servers. Thus, IMS APNs acquired in two successiveregistrations are different, addresses for IMS servers acquired in twoadjacent registrations are different, so that the number of times thatthe IMS registration is repeatedly refused by an IMS servercorresponding to one address for the IMS registration is reduced whenthe first preset threshold is equal to the second value. Thus, on theone hand, the number of times that the IMS registration is repeatedlyperformed is reduced when the IMS server refuses the IMS registration,and on the other hand, load balancing can be implemented betweendifferent IMS servers.

In some aspects, the method may further include that:

an attach request is sent to the network side; and

an attach accepted returned by the network side according to the attachrequest is received.

S11 may include that:

It is determined whether the network side supports the IMS serviceaccording to an IMS service support indication field carried in theattach request.

After the terminal is powered on or switches out of the flight mode, theterminal will automatically send an attach request to the network side.If the network side allows the terminal to attach, an attach acceptedmay be sent to the terminal. The attach accepted indicates accepting theattachment of terminal. In addition, the attach accepted may carry anIMS service support indication field which indicates whether the networkside supports the IMS service.

For example, in some aspects, the IMS service support indication fieldmay be an IMSVoPS field. When the value of the IMSVoPS field is “IMS VoPS session in S1 Mode supported”, it indicates that the network sidesupports the IMS service.

S11 may include that: the attach accepted is read and parsed, and it isdetermined whether the network side supports the IMS service accordingto the content of the IMS service support indication field.

After the terminal is successfully attached to the network, the terminalwill establish a connection with the network side and enter a connectedstate. At the same time, the terminal will complete the IMS registrationthrough the execution of steps S11 to S15. The terminal may perform anyinformation interaction with the base station through entering theconnected state. High-quality voice services may be initiated by theterminal through the IMS registration. Thus, the establishment processof the connection between the terminal and the network side may beperformed in parallel with the IMS registration, so that after theterminal is turned on or exits the flight mode, it can enter theinitialization of various functions as much as possible, thereby makingusers able to respond as quickly as possible when using variousfunctions.

In some aspects, S12 may include that: when the network side supportsthe IMS service, an address for the IMS registration is acquiredaccording to an IMS APN to obtain an IP address of the terminal and anIP address of an IMS server.

The operation that an IMS registration is performed according to theacquired address for the IMS registration may include that:

an IMS registration request is sent to the application server with an IPaddress of the terminal as a source address and an IP address of the IMSserver as a destination address; and

a registration response returned by the application server according tothe IMS registration request is received.

The registration response may be a response indicating registrationsuccess or a response indicating registration failure. If theregistration response is a response indicating registration failure, theregistration response may also carry a reason for the failure of the IMSregistration. Thus, the terminal may dynamically determine the firstpreset threshold according to the reason.

As illustrated in FIG. 4, the present aspect also provides a device forIMS registration, applied to a terminal. The device may include:

a first determination module 11, configured to determine whether anetwork side supports an IMS service;

an acquisition module 12, configured to acquire, when the network sidesupports the IMS service, an address for the IMS registration accordingto an IMS APN; and

a registration module 13, configured to perform the IMS registrationaccording to the acquired address for the IMS registration.

In some aspects, the first determination module 11, the acquisitionmodule 12 and the registration module 13 may be program modules. Afterbeing executed by the processor, the program modules may implementoperations corresponding to the respective modules.

In some other aspects, the first determination module 11, theacquisition module 12 and the registration module 13 may be combinedmodules of software and hardware, which include but not limited toprogrammable arrays. The programmable arrays include, but are notlimited to, complex programmable arrays or field programmable arrays.

In some aspects, the first determination module 11, the acquisitionmodule 12 and the registration module 13 may be pure hardware modules,which include but are not limited to Application Specific IntegratedCircuit (ASIC).

In some aspects, the registration module 13 is further configured toinitiate an IMS re-registration when the number of times that the IMSregistration is performed does not reach a first preset threshold.

In some other aspects, the acquisition module is further configured tore-acquire, when the number of times that the IMS registration isperformed reaches the first preset threshold, an address for the IMSregistration and to initiate the IMS registration according to there-acquired address for the IMS registration.

In some aspects, the acquisition module 12 is further configured todetermine whether the number of times that acquisition for the addressfor the IMS registration is performed reaches a second preset threshold,and to re-acquire, when the number of times that the acquisition isperformed does not reach the second preset threshold, an address for theIMS registration.

In some aspects, the device may further include:

a first control module, configured to control, when the number of timesthat the acquisition is performed reaches the second preset threshold,the terminal to enter a flight mode;

a second control module, configured to control, after the terminalenters the flight mode for a predetermined duration, the terminal toexit the flight mode; and

an attach module, configured to perform, after the terminal exits theflight mode, network attach.

The first determination module 11 is configured to determine, after theterminal is attached to a network, whether the network side supports theIMS service.

In some aspects, the device may further include:

a first receiving module, configured to receive a reason for a failureof the IMS registration; and

a second determination module, configured to determine, according to thereason, the first preset threshold.

In some aspects, the second determination module is configured todetermine that the first preset threshold has a first value when thereason for the failure of the IMS registration is that a registrationrequest of the IMS registration is lost; and to determine that the firstpreset threshold has a second value when the reason for the failure ofthe IMS registration is that an IMS server refuses to register. Thesecond value is less than the first value.

In some aspects, the device may further include:

a first sending module, configured to send an attach request to thenetwork side; and

a second receiving module, configured to receive an attach acceptedreturned by the network side according to the attach request.

The first determination module 11 is configured to determine whether thenetwork side supports the IMS service according to an IMS servicesupport indication field carried in the attach request.

In some aspects, the acquisition module 12 is configured to acquire,when the network side supports the IMS service, an address for the IMSregistration according to an IMS APN to obtain an IP address of theterminal and an IP address of an IMS server.

With regard to the device in the above aspects, the specific manner inwhich the respective modules perform the operations has been describedin detail in the aspect relating to the method, and will not beexplained in detail herein.

An example is provided below in combination with any of the aboveaspects:

Example 1

During an attach process, a terminal will receive the confirmation froma network side about whether the network side supports an IMS service.

An Application Processor (AP) of the terminal initiates establishment ofan IMS APN according to a report of the bottom, and waits for the bottomto report a state of the IMS registration.

After the IMS APN is established, a modem of the terminal initiates anIMS registration process. If the IMS registration fails, the number oftimes that an IMS registration request is re-sent is set according todifferent reason values, and an IMS registration request is re-sent.

If the registration fails, an indication of registration failure isreported to the AP.

If the registration is successful, an indication of registration successis reported to the AP.

After the AP receives the indication of registration failure reportedfrom the modem, the number of times that an IMS APN establishmentprocess is re-initiated may be set to re-initiate an IMS APNestablishment process and trigger the IMS registration process of thebottom.

An aspect of the present disclosure also provides a terminal, which mayinclude:

a processor; and

a memory configured to store instructions executable for the processor,

where the processor is configured to perform the method for IMSregistration provided in any of the preceding technical solutions.

Specifically, the processor is configured to implement, by executing theexecutable instructions, the following steps:

it is determined whether a network side supports an IMS service;

when the network side supports the IMS service, an address for the IMSregistration is acquired according to an IMS APN;

an IMS registration is performed according to the acquired address forthe IMS registration; and

when the IMS registration fails, an IMS re-registration is performed.

Further, the operation that the IMS re-registration is initiated whenthe IMS registration fails may include that:

when the number of times that the IMS registration is performed does notreach a first preset threshold, an IMS re-registration is initiated.

Further, when the number of times that the IMS registration is performedreaches the first preset threshold, an address for the IMS registrationis re-acquired, and an IMS registration is initiated according to there-acquired address for the IMS registration.

Further, the operation that the address for the IMS registration isre-acquired and the IMS registration is initiated according to there-acquired address for the IMS registration when the number of timesthat the IMS registration is performed reaches the first presetthreshold may include that:

it is determined whether a number of times that acquisition for theaddress for the IMS registration is performed reaches a second presetthreshold; and

when the number of times that the acquisition is performed does notreach the second preset threshold, the address for the IMS registrationis re-acquired.

Further, when the number of times that the acquisition is performedreaches the second preset threshold, the terminal is controlled to entera flight mode.

After the terminal enters the flight mode for a predetermined duration,the terminal is controlled to exit the flight mode.

After the terminal exits the flight mode, network attach is performed.

The operation that it is determined whether a network side supports anIMS service may include that:

after the terminal is attached to a network, it is determined whetherthe network side supports the IMS service.

Further, a reason for a failure of the IMS registration is received.

The first preset threshold is determined according to the reason.

Further, the operation that the first preset threshold is determinedaccording to the reason may include that:

when the reason for a failure of the IMS registration is that aregistration request of the IMS registration is lost, it is determinedthat the first preset threshold has a first value; and

when the reason for a failure of the IMS registration is that an IMSserver refuses to register, it is determined that the first presetthreshold has a second value, the second value is less than the firstvalue.

Further, an attach request is sent to the network side.

An attach accepted returned by the network side according to the attachrequest is received.

The operation that it is determined whether the network side supportsthe IMS service may include that:

it is determined whether the network side supports the IMS serviceaccording to an IMS service support indication field carried in theattach request.

Further, the operation that the address for the IMS registration isacquired according to an IMS APN when the network side supports the IMSservice may include that:

a PDN connection request is sent to the network side; and

a connection response returned by the network side according to the PDNconnection request is received, the connection response carries anaddress for the IMS registration.

The operation that an IMS registration is performed according to theacquired address for the IMS registration may include that:

an IMS registration request is sent to the application server with an IPaddress of the terminal as a source address and an IP address of the IMSserver as a destination address; and

a registration response returned by the application server according tothe IMS registration request is received.

FIG. 5 is a block diagram illustrating a terminal 800 for an IMSregistration according to an exemplary aspect. For example, the terminal800 may be a mobile phone, a computer, a digital broadcast terminal, amessaging device, a gaming console, a tablet, a medical device, exerciseequipment, a personal digital assistant, and the like.

Referring to FIG. 5, the terminal 800 may include one or more of thefollowing components: a processing component 802, a memory 804, a powercomponent 806, a multimedia component 808, an audio component 810, anInput/Output (I/O) interface 812, a sensor component 814, and acommunication component 816.

The processing component 802 typically controls overall operations ofthe terminal 800, such as operations associated with display, telephonecalls, data communications, camera operations, and recording operations.The processing component 802 may include one or more processors 820 forexecuting instructions to complete all or part of the steps in the abovedescribed methods. Moreover, the processing component 802 may includeone or more modules which facilitate the interaction between theprocessing component 802 and other components. For example, theprocessing component 802 may include a multimedia module to facilitatethe interaction between the multimedia component 808 and the processingcomponent 802.

The memory 804 is configured to store various types of data to supportoperations on the device 800. Examples of such data include instructionsfor any application or method operated on the terminal 800, contactdata, phonebook data, messages, pictures, video, etc. The memory 804 maybe implemented using any type of volatile or non-volatile memorydevices, or a combination thereof, such as a Static Random Access Memory(SRAM), an Electrically Erasable Programmable Read-Only Memory (EEPROM),an Erasable Programmable Read-Only Memory (EPROM), a ProgrammableRead-Only Memory (PROM), a Read-Only Memory (ROM), a magnetic memory, aflash memory, a magnetic disk or an optical disk.

The power component 806 provides power to various components of theterminal 800. The power component 806 may include a power managementsystem, one or more power sources, and any other components which areassociated with the generation, management and distribution of power forthe terminal 800.

The multimedia component 808 includes a screen providing an outputinterface between the terminal 800 and a user. In some aspects, thescreen may include a Liquid Crystal Display (LCD) and a Touch Panel(TP). If the screen includes the TP, the screen may be implemented as atouch screen to receive an input signal from the user. The TP includesone or more touch sensors to sense touches, swipes and gestures on theTP. The touch sensors may not only sense a boundary of a touch or swipeaction, but also detect the duration and pressure which are associatedwith the touch or swipe action. In some aspects, the multimediacomponent 808 includes a front camera and/or a rear camera. The frontcamera and/or the rear camera may receive external multimedia data whenthe device 800 is in an operation mode, such as a photographing mode ora video mode. Each of the front camera and the rear camera may be afixed optical lens system or may have focusing and optical zoomingcapabilities.

The audio component 810 is configured to output and/or input audiosignals. For example, the audio component 810 includes a Microphone(MIC). The MIC is configured to receive an external audio signal whenthe terminal 800 is in an operation mode, such as a call mode, arecording mode, and a voice recognition mode. The received audio signalmay be further stored in the memory 804 or transmitted via thecommunication component 816. In some aspects, the audio component 810further includes a speaker for outputting the audio signal.

The I/O interface 812 provides an interface between the processingcomponent 802 and peripheral interface modules, such as a keyboard, aclick wheel, or buttons. The buttons may include, but are not limitedto, a home button, a volume button, a starting button, and a lockingbutton.

The sensor component 814 includes one or more sensors for providingvarious aspects of status assessments for the terminal 800. For example,the sensor component 814 may detect an on/off state of the device 800and relative positioning of components. For example, the component is adisplay and small keyboard of the terminal 800. The sensor component 814may further detect the position change of the terminal 800 or theposition change of an component of the terminal 800, presence or absenceof a contact between the user and the terminal 800, orientation oracceleration/deceleration of the terminal 800, and the temperaturechange of the terminal 800. The sensor component 814 may include aproximity sensor which is configured to detect presence of a nearbyobject without any physical contact. The sensor component 814 may alsoinclude a light sensor, such as a Complementary Metal OxideSemiconductor (CMOS) or Charge Coupled Device (CCD) image sensor whichis configured for being used in an imaging application. In some aspects,the sensor component 814 may also include an acceleration sensor, agyroscope sensor, a magnetic sensor, a pressure sensor or a temperaturesensor.

The communication component 816 is configured to facilitate a wired orwireless communication between the terminal 800 and other devices. Theterminal 800 may access a wireless network based on a communicationstandard, such as WiFi, 2G or 3G, or a combination thereof. In anexemplary aspect, the communication component 816 receives a broadcastsignal or broadcast related information from an external broadcastmanagement system via a broadcast channel. In an exemplary aspect, thecommunication component 816 further includes a Near Field Communication(NFC) module to facilitate short-range communications. For example, theNFC module may be implemented based on a Radio Frequency Identification(RFID) technology, an Infrared Data Association (IrDA) technology, anUltra-Wideband (UWB) technology, a Bluetooth (BT) technology, and othertechnologies.

In exemplary aspects, the terminal 800 may be implemented by one or moreApplication Specific Integrated Circuits (ASICs), Digital SignalProcessors (DSPs), Digital Signal Processing Devices (DSPDs),Programmable Logic Devices (PLDs), Field Programmable Gate Arrays(FPGAs), controllers, micro-controllers, microprocessors, or otherelectronic elements, for performing the above described methods.

In exemplary aspects, there is also provided a non-transitory computerreadable storage medium including instructions, such as the memory 804including instructions, which are executable by the processor 820 of theterminal 800 to perform the above described methods. For example, thenon-transitory computer readable storage medium may be a ROM, a RandomAccess Memory (RAM), a Compact Disc Read-Only Memory (CD-ROM), amagnetic tape, a floppy disc, an optical data storage device and thelike.

According to an aspect of the present disclosure, there is also provideda non-transitory computer readable storage medium having storedinstructions that when being executed by a processor of a mobileterminal, enables the terminal to perform the method for IMSregistration. The method may be the preceding IMS registration methodthat is applied to a terminal and provided in the respective technicalsolutions. The method may specifically include that:

it is determined whether a network side supports an IMS service;

when the network side supports the IMS service, an address for the IMSregistration is acquired according to an IMS APN;

the IMS registration is performed according to the acquired address;

when the IMS registration fails, it is determined whether an addressre-acquisition condition is met; and

when the address re-acquisition condition is met, an address for the IMSregistration is re-acquired, and the IMS registration is re-performed.

Further, the operation that it is determined whether an addressre-acquisition condition is met includes:

when the number of times that the IMS registration is performed reachesa first preset threshold, it is determined that the addressre-acquisition condition is met.

Further, when the IMS registration fails and the number of times thatthe IMS registration is performed does not reach the first presetthreshold, the IMS re-registration is performed.

Further, the operation that the address for the IMS registration isre-acquired and the IMS registration is re-performed when the addressre-acquisition condition is met may include that:

it is determined whether the number of times that acquisition for theaddress for the IMS registration is performed reaches a second presetthreshold; and

when the number of times that the acquisition is performed does notreach the second preset threshold, an address for the IMS registrationis re-acquired.

Further, the method may further include that:

when the number of times that the acquisition is performed reaches thesecond preset threshold, the terminal is controlled to enter a flightmode;

after the terminal enters the flight mode for a predetermined duration,the terminal is controlled to exit the flight mode; and

after the terminal exits the flight mode, network attach is performed.

The operation that it is determined whether the network side supportsthe IMS service may include that:

after the terminal is attached to a network, it is determined whetherthe network side supports the IMS service.

Further, the method may further include that:

a reason for a failure of the IMS registration is received; and

the first preset threshold is determined according to the reason.

Further, the operation that the first preset threshold is determinedaccording to the reason may include that:

when the reason for the failure of the IMS registration is that aregistration request of the IMS registration is lost, it is determinedthat the first preset threshold has a first value; and

when the reason for the failure of the IMS registration is that an IMSserver refuses to register, it is determined that the first presetthreshold has a second value, the second value is less than the firstvalue.

Further, the method may further include that:

an attach request is sent to the network side; and

an attach accepted returned by the network side according to the attachrequest is received.

The operation that it is determined whether the network side supportsthe IMS service may include that:

it is determined whether the network side supports the IMS serviceaccording to an IMS service support indication field carried in theattach request.

Further, the operation that the address for the IMS registration isacquired according to an IMS APN when the network side supports the IMSservice may include that:

a PDN connection request is sent to the network side; and

a connection response returned by the network side according to the PDNconnection request is received, the connection response carries an IMSregistered address.

It is noted that the various modules, sub-modules, units, and componentsin the present disclosure can be implemented using any suitabletechnology. For example, a module may be implemented using circuitry,such as an integrated circuit (IC). As another example, a module may beimplemented as a processing circuit executing software instructions.

Other aspects of the disclosure will be apparent to those skilled in theart from consideration of the specification and practice of thedisclosure disclosed here. This application is intended to cover anyvariations, uses, or adaptations of the disclosure following the generalprinciples thereof and including such departures from the disclosure ascome within known or customary practice in the art. It is intended thatthe specification and examples be considered as exemplary only, with atrue scope and spirit of the disclosure being indicated by the followingclaims.

It will be appreciated that the disclosure is not limited to the exactconstruction that has been described above and illustrated in theaccompanying drawings, and that various modifications and changes can bemade without departing from the scope thereof. It is intended that thescope of the disclosure only be limited by the appended claims.

What is claimed is:
 1. A method for Internet Protocol MultimediaSubsystem (IMS) registration, the method being applied to a terminal,and the method comprising: determining whether a network side supportsan IMS service; acquiring, based on an IMS Access Point Name (APN), anaddress for the IMS registration when the network side supports the IMSservice; performing the IMS registration based on the acquired addressfor the IMS registration; and initiating an IMS re-registration when theIMS registration fails.
 2. The method of claim 1, wherein initiating theIMS re-registration when the IMS registration fails comprises:initiating the IMS re-registration when a number of times that the IMSregistration is performed does not reach a first preset threshold. 3.The method of claim 2, further comprising: re-acquiring an address foran IMS registration when the number of times that the IMS registrationis performed reaches the first preset threshold; and initiating the IMSregistration based on the re-acquired address for the IMS registration.4. The method of claim 3, wherein re-acquiring the address for the IMSregistration when the number of times that the IMS registration isperformed reaches the first preset threshold comprises: determiningwhether a number of times that acquisition for the address the IMSregistration is performed reaches a second preset threshold; andre-acquiring the address for the IMS registration when the number oftimes that the acquisition is performed does not reach the second presetthreshold.
 5. The method of claim 4, further comprising: controlling theterminal to enter a flight mode when the number of times that theacquisition is performed reaches the second preset threshold;controlling the terminal to exit the flight mode after the terminalenters the flight mode for a predetermined duration; and performingnetwork attach after the terminal exits the flight mode, whereindetermining whether the network side supports the IMS service comprisesdetermining whether the network side supports the IMS service after theterminal is attached to a network.
 6. The method of claim 1, furthercomprising: receiving a reason for a failure of the IMS registration;and determining the first preset threshold based on the reason.
 7. Themethod of claim 6, wherein determining the first preset threshold basedon the reason comprises: determining that the first preset threshold hasa first value when the reason for the failure of the IMS registration isthat a registration request of the IMS registration is lost; anddetermining that the first preset threshold has a second value when thereason for the failure of the IMS registration is that an IMS serverrefuses to register, wherein the second value is less than the firstvalue.
 8. The method of claim 1, further comprising: sending an attachrequest to the network side; receiving an attach acceptance from thenetwork side based on the attach request; and determining whether thenetwork side supports the IMS service based on an IMS service supportindication field carried in the attach request.
 9. The method of claim1, wherein acquiring, based on the IMS APN, the address for the IMSregistration when the network side supports the IMS service comprises:sending a Public Data Network (PDN) connection request to the networkside when the network side supports the IMS service; and receiving aconnection response from the network side based on the PDN connectionrequest, wherein the connection response carries an address for the IMSregistration.
 10. A device for Internet Protocol Multimedia Subsystem(IMS) registration, the device being applied to a terminal, and thedevice comprising: a processor; and a memory configured to storeinstructions executable for the processor, wherein the processor isconfigured to: determine whether a network side supports an IMS service;acquire, based on an IMS Access Point Name (APN), an address for the IMSregistration when the network side supports the IMS service; perform theIMS registration based on the acquired address for the IMS registration;and initiate an IMS re-registration when the IMS registration fails. 11.The device of claim 10, wherein the processor is further configured toinitiate the IMS re-registration when a number of times that the IMSregistration is performed does not reach a first preset threshold. 12.The device of claim 1, wherein the processor is configured to:re-acquire an address for the IMS registration when the number of timesthat the IMS registration is performed reaches the first presetthreshold; and initiate the IMS registration based on the re-acquiredaddress for the IMS registration.
 13. The device of claim 11, whereinthe processor is further configured to: determine whether a number oftimes that acquisition for the address for the IMS registration isperformed reaches a second preset threshold; and re-acquire the addressfor the IMS registration when the number of times that the acquisitionis performed does not reach the second preset threshold.
 14. The deviceof claim 13, wherein the processor is further configured to: control theterminal to enter a flight mode when the number of times that theacquisition is performed reaches the second preset threshold; controlthe terminal to exit the flight mode after the terminal enters theflight mode for a predetermined duration; perform network attach afterthe terminal exits the flight mode; and determine whether the networkside supports the IMS service after the terminal is attached to anetwork.
 15. The device of any one of claim 10, wherein the processor isfurther configured to: receive a reason for a failure of the IMSregistration; and determine the first preset threshold based on thereason.
 16. The device of claim 15, wherein the processor is furtherconfigured to: determine that the first preset threshold has a firstvalue when the reason for the failure of the IMS registration is that aregistration request of the IMS registration is lost; and determine thatthe first preset threshold has a second value when the reason for thefailure of the IMS registration is that an IMS server refuses toregister, wherein the second value is less than the first value.
 17. Thedevice of claim 10, wherein the processor is further configured to: sendan attach request to the network side; receive an attach acceptedreturned by the network side based on the attach request; and determinewhether the network side supports the IMS service based on an IMSservice support indication field carried in the attach request.
 18. Thedevice of claim 10, wherein the processor is further configured to: senda Public Data Network (PDN) connection request to the network side whenthe network side supports the IMS service; and receive a connectionresponse returned by the network side based on the PDN connectionrequest, wherein the connection response carries an address for the IMSregistration.
 19. A non-transitory computer-readable storage mediumstoring instructions that, when executed by a processor of a terminal,cause the terminal to: determine whether a network side supports an IMSservice; acquire, based on an IMS Access Point Name (APN), an addressfor the IMS registration when the network side supports the IMS service;perform the IMS registration based on the acquired address for the IMSregistration; and initiate an IMS re-registration when the IMSregistration fails.